Biosensors have wide applicability, such as medical diagnostics, infectious diseases, environmental sensing and food contamination, by detecting proteins, enzymes, bacteria, toxins, drugs, pollutants, DNA, etc. The development of better biosensors will have far-reaching societal impact, improving both health care and quality of life. We propose to develop an integrating multi-waveguide biosensor, where the illumination of the luminescent species on the sensing surface is not based on evanescent waves. The biosensor is capable of: - Low limits of determination - High sensitivity - High selectivity - Simultaneous analysis of multiple analytes - Low interference between waveguides, and - Enhanced discrimination between background and emitted signal. Preliminary experiments have demonstrated some of these features. The proposed research will optimize, fabricate and test this new type of biosensor. The Phase I research will: develop a method to analyze fluorescence on waveguide surfaces and implement it in a ray tracing code, applying the method to optimize waveguide designs, fabricate the best waveguide designs, experimentally test the waveguides with analyte, and compare the experimental data to reference experimental data and simulation results. PROPOSED COMMERCIAL APPLICATIONS: Biosensors can be applied to medical diagnostics, infectious diseases, environmental sensing and food contamination, to detect proteins, enzymes, bacteria, antibodies, toxins, drugs, pollutants, etc. The market is over $10 billion per year.